From 2a84e34fb0feff085dcf43eae5de1bf6f8d35d53 Mon Sep 17 00:00:00 2001
From: cbdev <cb@cbcdn.com>
Date: Sun, 9 Jul 2023 13:57:01 +0200
Subject: Sanitize tag data, pass dynamic data to commands
---
command.c | 20 +++++++++++---------
reader.c | 19 +++++++++++++++++++
2 files changed, 30 insertions(+), 9 deletions(-)
diff --git a/command.c b/command.c
index 3dc07e6..869c0a6 100644
--- a/command.c
+++ b/command.c
@@ -153,12 +153,12 @@ void command_reap(){
} while(status);
}
-static int command_spawn(command_t* cmd, char* command_name, char* command_static, size_t arg_length){
+static int command_spawn(command_t* cmd, char* command_name, char* command_static){
char* workdir = config_get("command", "chdir");
char* handler = config_get("command", "handler");
+ char tag_uid[12] = "", dynsize[10] = "";
size_t bytes;
- char tag_uid[12] = "";
- char dynsize[10] = "";
+ char* dynamic = (cmd->tag->dynamic_length) ? calloc(cmd->tag->dynamic_length + 1, sizeof(uint8_t)) : NULL;
printf("Starting command %s, static %s\n", command_name, command_static);
if(pipe(cmd->iopipe)){
@@ -203,12 +203,16 @@ static int command_spawn(command_t* cmd, char* command_name, char* command_stati
setenv("TAG_UID", tag_uid, 1);
setenv("MAX_DATA_LENGTH", dynsize, 1);
+ if(dynamic){
+ memcpy(dynamic, cmd->tag->dynamic_data, cmd->tag->dynamic_length);
+ }
+
//run actual command
if(handler){
- execl(handler, handler, command_name, command_static, NULL);
+ execl(handler, handler, command_name, command_static, dynamic, NULL);
}
else{
- execl(command_name, command_name, command_static, NULL);
+ execl(command_name, command_name, command_static, dynamic, NULL);
}
perror("child/exec");
_exit(1);
@@ -223,7 +227,7 @@ static int command_spawn(command_t* cmd, char* command_name, char* command_stati
}
int command_start(nfc_tag_info_t* info){
- size_t n = 0, p = ncommands, arg_length = 0;
+ size_t n = 0, p = ncommands;
uint8_t* command_name = NULL, *command_static = NULL;
for(n = 0; n < ncommands; n++){
@@ -257,7 +261,6 @@ int command_start(nfc_tag_info_t* info){
command_name[n] = 0;
if(info->static_length - n > 1){
command_static = command_name + n + 1;
- arg_length = info->static_length - n - 1;
}
break;
}
@@ -268,7 +271,6 @@ int command_start(nfc_tag_info_t* info){
free(command_name);
return 1;
}
- //FIXME might want to parse out any non-graphs
if(p == ncommands){
commands = realloc(commands, (p + 1) * sizeof(command_t));
@@ -284,7 +286,7 @@ int command_start(nfc_tag_info_t* info){
commands[p].tag = info;
commands[p].input_head = 0;
- if(command_spawn(commands + p, (char*) command_name, (char*) command_static, arg_length)){
+ if(command_spawn(commands + p, (char*) command_name, (char*) command_static)){
//TODO clean up and free command instance
}
diff --git a/reader.c b/reader.c
index 2c3a06b..32b17f0 100644
--- a/reader.c
+++ b/reader.c
@@ -4,6 +4,7 @@
#include <sys/timerfd.h>
#include <unistd.h>
#include <string.h>
+#include <ctype.h>
#include "nfcommander.h"
#include "reader.h"
@@ -38,6 +39,21 @@ static struct {
nfc_tag_info_t info;
} tags[MAX_TAGS] = { 0 };
+static void tag_data_sanitize(nfc_tag_info_t* tag){
+ size_t n = 0;
+ for(n = 0; n < tag->static_length; n++){
+ if(tag->static_data[n] && !isprint(tag->static_data[n])){
+ tag->static_data[n] = ' ';
+ }
+ }
+
+ for(n = 0; n < tag->dynamic_length; n++){
+ if(tag->dynamic_data[n] && !isprint(tag->dynamic_data[n])){
+ tag->dynamic_data[n] = ' ';
+ }
+ }
+}
+
static int reader_init_backend(){
char plugin[MAX_PLUGIN_PATH] = "";
char* reader = config_get("nfc", "reader");
@@ -201,6 +217,7 @@ int reader_tag_present(uint8_t flags, nfc_tag_info_t* tag){
if(flags & TAG_STATUS_FLAGS){
memcpy(&(tags[n].info), tag, sizeof(nfc_tag_info_t));
tags[n].flags |= flags;
+ tag_data_sanitize(&(tags[n].info));
return 0;
}
//if data has not yet been fully read, request a full read
@@ -209,7 +226,9 @@ int reader_tag_present(uint8_t flags, nfc_tag_info_t* tag){
if(tags[n].flags & (FLAG_WRITE_FULL | FLAG_WRITE_DYNAMIC)){
flags = tags[n].flags;
+ printf("Requesting %s data write on tag %lu\n", (flags & FLAG_WRITE_FULL) ? "full" : "partial", n);
tags[n].flags &= ~(FLAG_WRITE_FULL | FLAG_WRITE_DYNAMIC);
+ tag_data_sanitize(&(tags[n].info));
//this is kinda dangerous as we hand the reader backend our pointers
memcpy(tag, &(tags[n].info), sizeof(nfc_tag_info_t));
--
cgit v1.2.3